package com.zwy.leetcode;

public class Maths {

    /**
     * 3的幂
     * @param n
     * @return
     */
    public boolean isPowerOfThree(int n) {
        if (n > 1)
            while (n % 3 == 0)
                n /= 3;
        return n == 1;
    }

    public int countPrimes(int n) {
        return 0;
    }

}
